JPH04123110A - Production control system - Google Patents

Abstract

PURPOSE:To execute in the lump the switching work by a small number of persons, and also, by the remote control by searching the inside of a storage means, based on an identification code read by a reading means, and instructing a transfer to a branch line to a switching means, in the case a branch instruction is written. CONSTITUTION:In a storage means (h), a branch instruction is written in advance by an operating means l. In such a state, an identification code of a carrying means (d) is read by a second reading means (m) in this side of a switching means (j). When the branch instruction is written in with respect to this identification code, the switching means (j) is controlled by processing of a decid-means (n), and the carrying means (d) is transferred to a branch carrying line (i). In such a way, the switching work to night strage can be executed by a small number of persons, and also, switching can be executed in the lump by the remote control.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a production control system suitable for use in, for example, a production line for painting the bodies of automobiles.

``Conventional technology'' On the line that paints automobile bodies, normally,
A large number of body models are available, and the paint colors are also diverse. Therefore, the operator must perform work on each body according to the model and specified color. Therefore, it is recommended that a code indicating the model and specified color of the body be written on the bodies flowing on the line, transport hangers, etc., and an identification card or the like attached thereto, so that the worker can visually check this identification card. Therefore, I am doing the prescribed work.

Incidentally, in a given process, the maximum number of bodies that can be put into the process (hereinafter referred to as the "expired number") is determined in advance. Therefore, if for some reason the number of bodies is likely to exceed the expiration number, it will be necessary to temporarily store the bodies before the process. Also,
In the body transport line, there are parts where it is necessary to leave a certain number of spaces available at the end of the day. Even in such a case, a part that absorbs and retains the body is required to create a space on the line.

Therefore, in such parts, night storage is provided for storing the body. and,
The body is transferred from the main line to the night storage by switching the trajectory of the hanger or cart that transfers the body using a predetermined switching device.

1.Problems to be Solved by the Invention"In the past, workers had to switch to night storage while monitoring the work situation, and it was necessary to place a worker at each switching point, which required a lot of manpower. There was a problem. Moreover, when there are few workers, the problem arises that they have to go to each night storage one by one to carry out the cut and dry work, making the work complicated.

The present invention has been made in view of the above-mentioned circumstances, and provides a production management system that allows switching to night storage to be performed by a small number of people (for example, - people) and that allows the switching to be performed all at once by remote control. The purpose is to

"Means for Solving the Problems" In order to solve the above problems, the present invention provides a transport means d for transporting the workpiece placed in the input section λ to the delivery section C, as shown in FIG. an identification code e attached to each of the transport means d; a first reading means f for reading the identification code e of the transport means d in the loading section a; and an input for inputting information regarding the workpiece to be placed. means g, and each time a workpiece is placed on the conveyance means dJ, the identification code e read by the first reading means f and the information inputted by the input means g are combined. a storage means for storing information, a branch conveyance path i which is arranged in parallel with the main conveyance path from the input section a to the discharge section C and temporarily retains the conveyance means d, and an inlet side of the branch conveyance path i. A switching means j is provided to switch between transporting the transporting means to the main transport path or the branching path i, and a branching command for transporting the transporting means d to the branching path i is written in the storage section. an operating means g, a second reading means m provided immediately before the switching means j and reading an identification code e of the conveying means d;
A determination is made that the storage means is searched based on the identification code e read by the second reading means m, and if a branch command is written, the switching means is instructed to move to the branch path i. and means n.

"Operation" A branch instruction is written in advance in the storage means by the operating means a. Then, the identification code of the conveying means d is read by the second reading means m in the hand of the switching means. If a branch command has been written to this identification code, the switching means j is controlled by the processing of the determining means n, and the transport means d is transported to the branch transport path i.

"Embodiments" Hereinafter, embodiments of the present invention will be described with reference to the drawings.

A: Structure of the Example ■ Outline of the Production Line in the Example FIG. 2 is a schematic configuration diagram showing a painting line in an example of the present invention. The process of this painting line is explained as follows.

After body B was temporarily stored at a welding stock shop,
Placed on the hanger conveyor (see Figure 4) and pre-processed]
transported to. Here, when pretreatment is performed, electrodeposition coating is performed through the steps of electrodeposition part 2 and electrodeposition part 3. next,
The seams of the iron plates are sole-treated with Sealer 4,
The undercoat section 5 processes the lower part of the floor.

It then passes through a sealer furnace 6 and reaches an inspection section 7, where the electrodeposition coating is inspected. After passing through the inspection section 7, it passes through an intermediate coating section 8 and an intermediate coating section 9, and is subjected to an intermediate coating treatment.

After the intermediate coating process, it passes through the color alignment storage 10 and reaches the inspection section 11, where the intermediate coating is inspected. Next, the designated color is applied in the top coat section 12 . Then, baking is performed in the top coat section 14, thereby completing the top coat process. After finishing the top coating, the body B undergoes various inspections in the inspection section 15, passes through the paint stocking area 18, and reaches the wax processing section 19, where wax is applied. The waxed body is delivered to a paint stocking station 20.

In the painting stock areas 18 and 20, the following process (
A rearrangement is performed to efficiently pay out body B on the military record line). In the military discipline process, the work in each process differs depending on the type of car, destination, destination, or type of obunyong, so efficiency is required in the order of bodies flowing through the line. Therefore, the paint stocks 18 and 20 are rearranged according to this request. The reason why the sorting work is carried out at two locations, paint stocking areas 18 and 20, is because sufficient sorting cannot be done at one location. The body B discharged from the paint stocking area 20 is
After being temporarily held at the military discipline stock area 21, it will move to the military discipline process. The Military Discipline Stockyard 21 can store about 100 deer bodies, and serves as a buffer for dispensing bodies. By providing a buffer function in this way, it is possible to gain time for parts procurement in the military discipline process or to cope with fluctuations in the throughput of the military discipline process.

Further, the electrodeposition night 22, the solar night 23, the intermediate coating night 24, and the top coating night 25 are night storages for retaining the body.

■Configuration of Control System Next, FIG. 3 is a block diagram showing the control system of this embodiment. In the figure, 30.313233 is a hanger conveyor that conveys the body B, and is provided in each of the input process, hand process, automation process, and delivery process. The input process is rT 1-ON shown in Figure 2.
The process from J to the front of the pretreatment section L is referred to as the hand process, and the hand process refers to the inspection sections 7, 11, and 15, and the automated process includes the sealer 4, underfoot section 5, intermediate coating section 8, top coating section 12, and wax treatment. 19, etc., and the dispensing process refers to the paint stocking area 20. In addition, in Fig. 3, the loading process, nodding process, automation process, and discharging process are simply arranged serially to simplify the explanation, but in reality, the nodding process and the automation process are They are arranged alternately as appropriate.

A large number of hangers 35 shown in FIG. 4 are attached to each hanger conveyor 30-33. The hanger 35 is adapted to circulate within each hanger conveyor 30-33. However, in reality, the hanger 35 is suspended from the hanger conveyors 30 to 33, but here, for the sake of simplicity, the hanger 35 is suspended from the hanger conveyors 30 to 33.
33.

Further, a hanger plate 36 is attached to the hanger 35, and eight windows as shown in FIG. 5 are set in the hanger plate 36. These eight windows are weighted as rlJ, r2jr4J, r8J, etc., and a predetermined identification code (hereinafter referred to as hanger number) is expressed depending on whether the window is open or closed. It has become. The hanger number is unique to each hanger and the same value is never set. The hanger number is read by a hanger reader 40 (first reading means) shown in FIG. The hanger leader 40 is located at the input section of each hanger container 30 to 33 and at a predetermined position (described later).
The tip of the hanger plate 36 is connected to the fifth
As shown in the figure, it is detected by a phototube 41, and at this timing, the opening of each window is examined.

Hanger conveyor 30.31132.33 shown in Figure 3
are installed in the input process, hand process, automated process (sealer, UDC, intermediate coat, top coat, WAX), and discharge process of the painting line, respectively, and the conveyor control panels 50, 51.
Its travel is controlled by 52 and 53. A card reader 55 is provided in the loading process to read the data on the magnetic card 56. The magnetic cart 56 stores various information regarding painting and assembly of the body B (hereinafter referred to as body information), and the magnetic cart 56 is transported together with the body B to the painting process. The printer 57 is a card reader 55
reads and prints out the body information so that the operator can visually check it. 58 is a transfer device that places the body on the hanger 35 of the hanger carrier 30, and when the body is placed by this transfer device,
A magnetic card 56 is inserted into the card reader 55 by an operator. The body information read from the card reader 55 is then transferred to the host computer 60.

A file 61 stores usage data, processing data, etc. of the host computer 60. The main computer 60 also communicates with a computer (personal computer) 64 via modems 62 and 63. The computer 64 is configured to perform data communication with the sequencer 70, and furthermore, the computer 64 is configured to perform data communication with the sequencer 70.
is the sequencer 71, and the sequencer 71 is the sequencer 72.
The sequencer 72 and the sequencer 73 each perform data communication.

65 to 67 shown in FIG. 3 are computers,
The sequencers 70 to 73 constitute a LAN (local area network). computer 65-6
7 has the same information in order to back up the sequencers 70 to 73.

The sequencers 70 to 73 are connected to the hanger conveyors 30 to 73, respectively.
33, and also has a shift register 80 shown in FIG. The hanger number read by each hanger reader 40 is input into the first stage of this shift register 80.

Furthermore, limit switches LS for detecting passage of the hanger 35 are provided at predetermined intervals on the hanger conveyor, and the storage area of the shift register 80 is divided corresponding to each limit switch LS. Sequencer 7
0 to 73 recognize the section divided by the limit switch LS as a zone, recognize the entire section of the soft register 80 as a block, and immediately recognize the position of each storage area of the shift register 80 as a positron. It has become. The shift register 80 is a so-called first-pack type, and when a hanger number is supplied to the first stage, it is sequentially shifted to the later stages as long as there is a free space. However, when shifting beyond the zone, use the limit switch L,
This is performed only when the passage of the hanger 35 is detected by S. That is, when the passage of the hanger is detected by the limit switch LS, the limit switch L
The hanger number in the last stage storage area of the zone before the boundary corresponding to S is shifted to the first stage storage area of the next zone.

Reference numeral 80 in FIG. 3 is a display that displays various displays to the operator working in the hand process under the control of the conhair control panel 51. 81 and 82 are a card reader and a printer, respectively, and the card reader 55 and printer 57 described above are
It has the same function as . The body information read by the card reader 81 is transferred to the next process, the military discipline line.

Next, 90, 91, and 92 are robots that perform various automatic operations in the automation process, and robot control panel 93.
Controlled by 94.95.

The stage mask board 96 is connected to each robot control board 93°94.
95, the job number is transferred as appropriate. Here, the job numbers are robots 90, 91, .
This code specifies the operation of 92. In addition, the stage mask boards 96 and 98 are the robot control boards for other stages (
(not shown). The job number is transferred from the model distribution board 100 to the line master board 99, and the line mask board 99 distributes and transfers it to each stage mask board 96-98. When the model distribution board 100 receives body information from the converter control board 52, it refers to an internal table, converts it into a job number, and transfers it to the line mask board 99. Note that the operation up to the time when the body information is output from the conveyor control panel 52 will be described later.

In the above configuration, sequencers 70 to 73, personal computer 6
4 to 67 and a terminal 68 are installed in the central control room. The terminal 68 displays management data transferred from the management computer 67, such as production volume and process flow rate.

Here, the configuration of the track switching device that switches the hanger conveyor 30 from the main line to the night storages 22 to 25 will be described.

FIG. 10 is a plan view showing the configuration of the track switching device. In this figure, 120 is a main line running from upstream to downstream, and 121 is a trolley. Trolley 1
Two trolleys 21 are provided at a predetermined distance apart from one hanger 35 in the front and back direction of the line, and the hangers 35 are suspended from these trolleys. 1
Reference numeral 22 denotes a branch plate, which is configured to be rotatable around a fulcrum A, and is normally located at the position shown by the solid line in the figure.

If the branch plate 122 is in the position indicated by the solid line, the Toro 1
, 1-121 are conveyed to the main line conveyor and go straight from the right end to the left end in the figure. Next, 123 is a branch cylinder, which is designed to retract the cylinder when branching.

When this cylinder is retracted, its driving force is applied to the member 12.
2a to the branch plate 122, and the branch plate 122 rotates counterclockwise to reach the position shown by the dashed line. As a result, the trolley 121 is connected to the branch plate 12.
2 and enter Nightline 125. At this time, the dog 126 provided on the trolley 121 is connected to the limit switch 126 provided on the inlet side of the night line 125.
Move actuator 7. This limit switch 12
7, it is detected whether the trolley 121 has entered the night line 125 or not.

130 is a cylinder, with a claw + at the tip of the cylinder rod.
It has 32. This cylinder 130 is connected to the trolley 1
When the trolley 21 enters the night line +25, the cylinder rod is extended to hook the dog 126 with the claw star 32, and then the cylinder rod is retracted to transfer the trolley 121 to the night line conveyor 131. The trolley 121 transferred to the nightline conveyor +31 is thereafter conveyed by the nightline conveyor +31. In FIG. 10, the hanger leader 40 (
a second reading means) is provided, and the incoming hanger 3
The hanger number 5 can be read.

Furthermore, the same device as above is used when transferring the hanger 35 from night storage to the main line. In this case, the operations are performed in the reverse order of the operations described above.

Next, the internal configuration of the computer 64 will be explained with reference to FIG. 11.

In the figure, 105 is a CPU that controls each part of the device, and operates according to the program in the program memory lot. M is a memory in which the hanger number and body information are stored, and the storage procedure will be described later.

+02 is a keyboard for issuing various instructions to the CPUIO 3; 103 is a CRT display device for displaying various displays under the control of the CPU 105; 104 is a communication interface, which connects the controllers 70 to 73 and the computer 6.
5-67 and CPtJ 105.

The CPU 105 reads from and writes to each shift register 80 in the sequencers 70 to 73 via the communication interface 104.

Further, respective output signals from the limit switch 127 and the hanger leader 40 shown in FIG.
5.

Furthermore, the CPU I O 5 controls the expansion and contraction of the cylinder 130 and the branch cylinder 123. A combination U consisting of branch nolinders 123 is provided at the entrance and exit sides of each night storage.

Further, the other computers 65, 66, and 67 have the same configuration as above.

B: Operation of the Embodiment Next, the operation of this embodiment using the above-mentioned configuration will be explained with reference to FIG.

■Hanger number tracking First, the body is transferred from the WBS shown in Figure 2 to the transfer device 58a.
By the hanger 35 of the input part of the hanger hanger bear 30
will be placed on. At this time, the operator inserts the magnetic card 56 of the body into the card reader 55. As a result, the body information is transferred to the host computer 60, and further,
It is transferred to computer 64 via modem 62,63.

On the other hand, a hanger reader 40 (see FIG. 4) provided at the input section of the hanger conveyor 30 reads the hanger number from the hanger plate 36 and sends it to the sequencer 70.
Transfer to. The sequencer 70 writes the transferred hanger number in the initial storage area of the first zone of the register 80 and transfers it to the computer 64. When the computer 64 is supplied with the hanger number, it stores this and body information as a pair in its internal memory. As a result, the relationship between the body and the bunker on which it is placed is saved as data. Thereafter, the above-described process is performed every time the body B is transferred to the hanger 35 by the transfer device 58λ, and as a result, the internal memory of the computer 64 stores the correspondence between the body to be loaded and the hanger number. To go.

Here, if we take as an example a case where the hanger number read by the hanger reader 40 is ■, ■, ■, etc., the internal memory of the computer 64 has the correspondence as shown in FIG. The relationship will be remembered. In the figure, M indicates an internal memory, and AI, A2, . . . indicate its storage area. For example, in the storage area AI, body information indicating that the body for domestic use, the car model is A, and the color is red is stored, as well as the hanger number ■ of the hanger on which this body is placed. .

On the other hand, the shift register 80 in the sequencer 70 performs the following processing. First, as shown in FIG. 8(a), hanger number 〇 is input into the first stage storage area. This hanger number ■ is sequentially shifted to the later stage and reaches the final stage of the zone (see figure (b)). Next, when the hanger number ■ is input, it is shifted to the later stage in the same manner as above and is stored in the storage area one stage before the final stage of the zone (see (c) in the same figure). In this way, soft register 8
The hanger number input as 0 is sequentially shifted to the next stage as long as there is empty space. However, in the above case, software that crosses the zone is not performed. Then, when the hanger 35 with the number ■ moves and its passage is detected by the first limit switch LS, the detection signal of this limit switch LS is transferred to the sequencer 70.

From this point, the sequencer 70 shifts the hanger number ■ to the first stage storage area of the next zone, as shown in FIG. 8(d). The hanger number (■) shifted in this way is then sequentially shifted to the next stage in the next zone. Also, in Moe's zone, the storage area of the last stage will be empty, so the hanger numbers ■, ■...
... are shifted to the next stage one stage at a time.

Next, proceed to convey body B, and hanger conveyor 30
The case where the image is transferred from the hanger conveyor 31 to the hanger conveyor 31 will be explained. For example, when the hanger with hanger number ■ reaches the delivery section of the hanger container 30, the body is transferred onto the transfer device 58b. At this time, the shift register 80
The hanger number ■ is stored in the storage area at the last stage, or the shift register 80 discards the hanger number ■ as the body B is transferred. Therefore, each hanger number in shift register 80 is shifted one stage at a time toward one stage.

Further, an identification number is set in advance in the transfer device 58b, and this identification number is stored in the sequencer 70 or the computer 64. Then, when body B is transferred, a signal indicating transfer is supplied to the computer 64 via the sequencer 70.
The hanger number in the storage area A1 shown in FIG. 7 is rewritten to the identification number of the transfer device 58b. For example, if the identification number is rloooj, it will be rewritten from ■ to rloooJ. Next, the body B is transferred from the transfer device 58b to the hanger 35 at the input section of the hanger conveyor 31. Then, the hanger number of this hanger 35 is detected by the hanger reader 40 in the input section of the hanger conveyor 31 and transferred to the sequencer 71. If the hanger number [stock] is detected, this hanger number [stock] is transferred to the sequencer 71.

The sequencer 71 transfers the hanger number [Co., Ltd.] to the fun computer 64 via the sequencer 70, and
Input to internal shift register 80.

As a result, the computer 64 rewrites the hanger number in the storage area A1 shown in FIG. 7 from rloooJ to [stock]. Further, the soft register 80 in the shift register 71 is the soft register 80 of the sequencer 70 described above.
Perform the same shift operation.

The above-mentioned operation is similarly performed when body B is transferred to another hanger conveyor. That is, when the hanger on which the body is placed is changed, the computer 64 rewrites the hanger number in the corresponding storage area in the memory M to a new one. Therefore, by referring to the memory M, it is possible to know what kind of body is placed on each hanger.

(2) Monitoring of tracking data As described above, each shift register 80 in the sequencers 70 to 73 shifts the hanger number in response to the movement of the hanger. That is, tracking of hanger numbers is performed. Each sequencer 70 to 73 is
The contents of the shift register 80 are transferred to the computers 65 to 67 at the timing when the body B is transferred to the hanger conveyor on the downstream side. This transfer is
This is performed for at least one of the numbers 5 to 67, thereby duplicating the hanger number (tracking data) in each shift register 80. If any of the sequencers 70 to 73 goes down, hanger number data is transferred from one of the computers 65 to 67 to the shift register 80 of that sequencer. This speeds up recovery.

Furthermore, by referring to the contents of each shift register 80 and the contents of the memory M, the computer computer 64 can recognize the block and zone in which the body exists.

■Automatic branch processing At the end of the work day or when there is a large number of removals of machines for the post-processing of night storage, the operator in the central control room performs the following processing.

First, the CRT display [103 (first
Figure 1) shows the line status. This display is performed based on the recognition of the location of each body obtained by monitoring the tracking data described above. Then, check the body to be switched to night storage (electrodeposition night 22, nura night 23, intermediate coating night 24, or top coating night 25) from the display screen, and enter the hanger number of the hanger 35 on which the body is placed using the keychain 1.
02, and input a command to switch the hanger 35 to night storage. As a result, "l" is set in the predetermined flag in the area of the memory M where the hanger number concerned is stored. Thereafter, the operator performs the same process as above for the hanger 35 to be switched to night storage. Note that the operator may recognize the body to be switched to night storage by visually observing the actual painting line.

Next, hanger 3 flagged by the above process
5 is transferred to the vicinity of the night storage, the hanger reader 40 shown in FIG. 1θ reads the hanger number. The read hanger number is supplied to the CPU 105, and the CPUIO3 searches the memory M using the hanger number as a key. If this search finds that the hanger is flagged,
The CPU I05 outputs a control signal that causes the branch cylinder 123 to retract. As a result, the branch cylinder 123
The branch plate 122 is rotated, and the hanger 35 is guided to the night line +25. Then, the dog 126 of the single hanger 35 guided by the night line 125 is detected by the limit switch 127, and a detection signal is supplied from the limit switch 127 to CPtJ I 05. As a result, the CPU 105
The cylinder 130 or cylinder rod is extended, and the claw 132 at the tip of the dog 126 is extended.
Hook it and pull it into Nightline 125. As a result, the hanger 35 is thereafter conveyed by the conveyor of the night line 125, and the switching is completed.

For hangers with flags set, switching is performed in the same manner as above, and when a hanger with no flags is set, the branch plate comes to the position shown by the solid line in Figure 1O, so that hanger is switched from the main line. Go straight on +20. In this way, a flag is set in advance and only one hanger is pulled into the night line 125. The drawn-in hangers 35 are sequentially conveyed inside the night line 125, and the hanger 35 at the beginning is transported inside the night line 125.
When it reaches near the exit 5, its movement is regulated by a stopper (path shown). The movement of the succeeding hanger 35 is restricted when it approaches the preceding hanger 35.

Next, when switching the hanger 35 in the night storage to the main line, the operator uses the keychain 102 to instruct the CPU 105 to that effect. As a result, a device similar to that shown in FIG. 1O operates in the opposite manner to that described above, transferring the hangers 35 one after the other to the main line.

C: Modification The following modifications can be made to the above-mentioned embodiment.

■Soft resistor 80 corresponding to limit switch LS
The shift register 80 may be divided into a plurality of zones, or the shift register 80 may not be divided unless there is a particular need.

(2) In the embodiment, a plurality of blocks are provided, but if the scale of the production line is small, a single block may be used.

(2) In the embodiment, rewriting of the memory M when transferring the body B between blocks is performed once by the transfer device 58a.
After rewriting the identification number to 58b, a new hanger number is written.

On the other hand, the identification number of the transfer device may be omitted, and when a new body B is placed on a new hanger, the hanger number j may be rewritten.

"Effects of the Invention" As explained above, according to the present invention, there are advantages in that switching to night storage can be performed by a small number of people and that switching can be performed all at once by remote control.

[Brief explanation of drawings]

Figure 1 is a functional block diagram showing the configuration of this invention, the second factor is a schematic configuration diagram showing the configuration of a painting line that is an embodiment of this invention, and Figure 3 is a control block diagram showing the control system of the same embodiment. Figure 4 is a schematic configuration diagram showing the vicinity of the input section of the hanger conveyor, Figure 5 is a front view showing the configuration of the hanger plate, Figure 6 is a conceptual diagram showing the shift register installed in the controller, and Figure 7 8 is an explanatory diagram illustrating the shift operation of the soft register 80, FIG. 9 is a schematic configuration diagram showing the configuration near the robot 90, and FIG. 10 is a diagram illustrating the structure of the hanger. FIG. 11 is a plan view showing the configuration of a switching device for switching the conveyance line, and FIG. 11 is a block diagram showing the configuration of the computer 64. 35... Hanger (transporting means), 36... Hanger plate (identification code), 40... Hunger league (first reading means, second reading means), 55...
... Card league (input means), M ... Memory (storage means), 102 ... Keyboard (operation means), 105 ... CPU (judgment means), 12
0... Main line (main conveyance path), 122...
- Branching plate (switching means), 123 Branching flick (switching means), 125-... Night line (branching conveyance path).

Claims (1)

[Claims] A transport means for transporting the workpiece placed in the input section to the output section, an identification code attached to each of the transport means, and a first system for reading the identification code of the transport means in the input section.
a reading means, an input means into which information regarding the workpiece to be placed is input, and an identification code read by the first reading means each time a workpiece is placed on the conveyance means. a storage means for storing a set of information inputted by the input means; a branch conveyance path which is arranged in parallel with the main conveyance path from the input section to the output section and temporarily retains the conveyance means; a switching means provided on the entrance side of the branch conveyance path for switching between transferring the conveyance means to the main conveyance path or to the branch path; and a branching instruction for transferring the conveyance means to the branch path in the storage section. an operating means for writing;
A second reading means is provided immediately before the switching means and reads an identification code of the conveyance means, and the second reading means searches the storage means based on the identification code read, and a branch instruction is written. 1. A production management system comprising: a determination means for instructing said switching means to transfer to a branching route if the production control system